Night Owls Vs Early Risers: A Difference in Intelligence?

If only my mother had read this article during my school years...

Some people are night owls, and others are morning larks. What makes the difference may be their levels of general intelligence.

Virtually all species in nature, from single-cell organisms to mammals, including humans, exhibit a daily cycle of activity called circadian rhythm. The circadian rhythm in mammals is regulated by two clusters of nerve cells called the suprachiasmatic nuclei (SCN) in the anterior hypothalamus. Geneticists have by now identified a set of genes that regulate the SCN and thus the circadian rhythm among mammals.

However, humans, unlike other mammalian species, have the unique ability, consciously and cognitively, to override their internal biological clock and its rhythmic outputs. In other words, at least for humans, circadian rhythm is not entirely a matter of genetics. Within broad genetic constraints, humans can choose what time to go to bed and get up. Humans can choose to be night owls or morning larks.

While there are some individual differences in the circadian rhythm, where some individuals are more nocturnal than others, humans are basically a diurnal (day-living) species. Humans rely very heavily on vision for navigation but, unlike genuinely nocturnal species, cannot see in the dark or under little lighting, and our ancestors did not have artificial lighting during the night until the domestication of fire. Any human in the ancestral environment up and about during the night would have been at risk of predation by nocturnal predators.

In the 10-volume compendium The Encyclopedia of World Cultures, which extensively catalogs all human cultures known to anthropology, there is no mention of nocturnal activities in any of the traditional cultures. There are no entries in the index for “nocturnal,” “night,” “evening,” “dark(ness),” and “all-night.” The few references to the “moon” are all religious in character, as in “moon deity,” “Mother Moon (deity),” and “moon worship.” The only exception is the “night courting,” which is a socially approved custom of premarital sex observed among the Danes and the Finns, which are entirely western cultures far outside of the ancestral environment.

Extensive ethnographies corroborate these observations and suggest that people in traditional societies usually rise shortly before dawn and go to sleep shortly after dusk, to take full advantage of the natural light provided by the sun. “Daily activities begin early in a Yanomamö village,” and “despite the inevitable last-minute visiting, things are usually quiet in the village by the time it is dark.” Among the Maasai in Kenya, “the day begins about 6 a.m., when the sun is about to rise,” and “most evenings are spent quietly chatting with family members indoors. If the moon is full then it is possible to see almost as well as during the day, and people take advantage of the light by staying up late and socializing a great deal.” Among the Ache in Paraguay, “after cooking and consuming food, evening is often the time of singing and joking. Eventually band members drift off to sleep, with one or two nuclear families around each fire.”

There is thus no indication in any of the ethnographic evidence that any sustained nocturnal activities occur in traditional societies, other than occasional conversations and singing, in these tribes. It is therefore reasonable to infer that our ancestors must also have limited their daily activities to daylight, and sustained nocturnal activities are largely evolutionarily novel. The Hypothesis would therefore predict that more intelligent individuals are more likely to be nocturnal than less intelligent individuals.

An analysis of a large representative sample of young Americans confirms this prediction. Net of a large number of social and demographic factors, more intelligent children grow up to be more nocturnal as adults than less intelligent children. Compared to their less intelligent counterparts, more intelligent individuals go to bed later on weeknights (when they have to get up at a certain time the next day) and on weekends (when they don’t), and they wake up later on weekdays (but not on weekends, for which the positive effect of childhood intelligence on adult nocturnality is not statistically significant). For example, those with a childhood IQ of less than 75 ("very dull") go to bed around 23:41 on weeknights in early adulthood, whereas those with a childhood IQ of over 125 ("very bright") go to bed around 00:29.

Full Article: http://www.psychologytoday.com/blog/the-scientific-fundamentalist/201005/why-night-owls-are-more-intelligent-morning-larks
Source: http://www.psychologytoday.com/

Meaning of unconscious mind

Consciousness by Robert Fludd, 1619

Problem of conscious and unconscious mind isn't new in philosophy – actually it was already known to antique philosophers (the unconsciousness concept was also used in the zombie thought experiment). The unconscious is closely related to the subconscious, the concept which is less controversial and was the main interest of Freud (it’s not true that Freud discovered subconscious/unconscious mind – the term unconscious mind had been already coined by Friedrich von Schelling). The unconscious mind is defined as automatic mental processes which are not available to introspection. I believe that consciousness and unconsciousness are crucial in understanding human’s nature and therefore should not be neglected by modern philosophy.

Friedrich von Schelling
(1775-1854)

You’re wondering what are the examples of unconscious mind (besides philosophical zombies)? Some say that reflexes, phobias or complexes belong to the unconscious. According to Sigmund Freud they also include dreams and even slips of tongue (watch your tongue from now on!). What is really interesting is that – at least according to psychoanalytic theory – dreams are not sensu stricto the unconscious. They are only signs or symptoms of its existence; that is why many psychoanalysts try to understand the symbolic meaning of the dreams in order to get the access to human’s unconsciousness. Another part of the unconscious is subliminal messages. This is quite a controversial issue since there is no agreement whether subliminal stimuli can actually alter the human’s behaviour or not, and if they can, it’s difficult to measure to what extent. What is meant by subliminal messages? These are sensory stimuli which can’t be consciously perceived. Imagine that you’re watching a presentation with a set of beautiful landscape pictures but from time to time a picture of a fearful face flashes; a picture is shown for a really short period of time, so short that you (read your consciousness) are not even able to notice it. Nevertheless a fearful face is seen by your subconscious mind and despite the fact you’re not being aware of the fact, your brain experiences anxiety.

The concept of unconsciousness was often rejected and criticised by many philosophers who claimed that it is invalid. I really like Erich Fromm’s opinion: The term ‘the unconscious’ is actually a mystification […]. There is no such thing as the unconscious; there are only experiences of which we are aware, and others of which we are not aware, that is, of which we are unconscious. If I hate a man because I am afraid of him, and if I am aware of my hate but not of my fear, we may say that my hate is conscious and that my fear is unconscious; still my fear does not lie in that mysterious place: 'the' unconscious.

This reminds me of a quite well known anecdote (I’m sure it has plenty of varieties, maybe you know one of them as well) about the discussion between a teacher and a student who has not really understood the concept of the cold and argued that in fact there is no such thing. He said to the teacher that it’s not possible to experience smaller or greater cold – you can experience smaller or bigger heat, you can also experience no heat (absolute zero) but you can't experience the cold itself. It turns out that the cold is in fact the lack of heat. Don’t you think that the same reasoning may be applied to the unconscious mind? Because to my mind we are still unconscious of the unconscious’s nature.

The Brain and Religious Experience

The article, “Religious factors and hippocampal atrophy in late life,” by Amy Owen and colleagues at Duke University represents an important advance in our growing understanding of the relationship between the brain and religion. The study, published March 30 in PLoS One, showed greater atrophy in the hippocampus in individuals who identify with specific religious groups as well as those with no religious affiliation. It is a surprising result, given that many prior studies have shown religion to have potentially beneficial effects on brain function, anxiety, and depression.

A number of studies have evaluated the acute effects of religious practices, such as meditation and prayer, on the human brain. A smaller number of studies have evaluated the longer term effects of religion on the brain. Such studies, like the present one, have focused on differences in brain volume or brain function in those people heavily engaged in meditation or spiritual practices compared to those who are not. And an even fewer number of studies have explored the longitudinal effects of doing meditation or spiritual practices by evaluating subjects at two different time points.

In this study, Owen et al. used MRI to measure the volume of the hippocampus, a central structure of the limbic system that is involved in emotion as well as in memory formation. They evaluated the MRIs of 268 men and women aged 58 and over, who were originally recruited for the NeuroCognitive Outcomes of Depression in the Elderly study, but who also answered several questions regarding their religious beliefs and affiliation. The study by Owen et al. is unique in that it focuses specifically on religious individuals compared to non-religious individuals. This study also broke down these individuals into those who are born again or who have had life-changing religious experiences.

The results showed significantly greater hippocampal atrophy in individuals reporting a life-changing religious experience. In addition, they found significantly greater hippocampal atrophy among born-again Protestants, Catholics, and those with no religious affiliation, compared with Protestants not identifying as born-again.

The authors offer the hypothesis that the greater hippocampal atrophy in selected religious groups might be related to stress. They argue that some individuals in the religious minority, or those who struggle with their beliefs, experience higher levels of stress. This causes a release of stress hormones that are known to depress the volume of the hippocampus over time. This might also explain the fact that both non-religious as well as some religious individuals have smaller hippocampal volumes.

This is an interesting hypothesis. Many studies have shown positive effects of religion and spirituality on mental health, but there are also plenty of examples of negative impacts. There is evidence that members of religious groups who are persecuted or in the minority might have markedly greater stress and anxiety as they try to navigate their own society. Other times, a person might perceive God to be punishing them and therefore have significant stress in the face of their religious struggle. Others experience religious struggle because of conflicting ideas with their religious tradition or their family. Even very positive, life-changing experiences might be difficult to incorporate into the individual’s prevailing religious belief system and this can also lead to stress and anxiety. Perceived religious transgressions can cause emotional and psychological anguish. This “religious” and “spiritual pain” can be difficult to distinguish from pure physical pain. And all of these phenomena can have potentially negative effects on the brain.

Thus, Owen and her colleagues certainly pose a plausible hypothesis. They also cite some of the limitations of their findings, such as the small sample size. More importantly, the causal relationship between brain findings and religion is difficult to clearly establish. Is it possible, for example, that those people with smaller hippocampal volumes are more likely to have specific religious attributes, drawing the causal arrow in the other direction? Further, it might be that the factors leading up to the life-changing events are important and not just the experience itself. Since brain atrophy reflects everything that happens to a person up to that point, one cannot definitively conclude that the most intense experience was in fact the thing that resulted in brain atrophy. So there are many potential factors that could lead to the reported results. (It is also somewhat problematic that stress itself did not correlate with hippocampal volumes since this was one of the potential hypotheses proposed by the authors and thus, appears to undercut the conclusions.) One might ask whether it is possible that people who are more religious suffer greater inherent stress, but that their religion actually helps to protect them somewhat. Religion is frequently cited as an important coping mechanism for dealing with stress.

This new study is intriguing and important. It makes us think more about the complexity of the relationship between religion and the brain. This field of scholarship, referred to as neurotheology, can greatly advance our understanding of religion, spirituality, and the brain. Continued studies of both the acute and chronic effects of religion on the brain will be highly valuable. For now, we can be certain that religion affects the brain--we just are not certain how.

Source: http://www.scientificamerican.com/article.cfm?id=religious-experiences-shrink-part-of-brain From: http://www.scientificamerican.com/